Turbine engine combustor with bolted swirlers

ABSTRACT

Aspects of the invention relate to a system for attaching a fuel swirler in a turbine engine combustor. According to embodiments of the invention, at least the axial upstream end of the fuel swirler can be attached to a combustor support frame using one or more fasteners, such as bolts. A radial bracket provided on the swirler to facilitate attachment. The axial downstream end of the swirler can be positioned within an opening defined in a swirler base plate or within an opening in a support plate. Aspects of the invention can reduce the time and cost associated with installation and replacement of fuel swirlers in a combustor while avoiding concerns associated with known welded pin attachment systems.

FIELD OF THE INVENTION

The invention relates in general to turbine engines and, morespecifically, to fuel swirlers in the combustor section of a turbineengine.

BACKGROUND OF THE INVENTION

The use of fuel swirlers in the combustor section of a turbine engine isknown. FIG. 1 shows an exemplary prior art fuel swirler 10 for a mainfuel nozzle 20. The fuel swirler 10 includes a substantially cylindricaltapered body 11. The fuel swirler 10 has a flared inlet end 12 and atapered outlet end 14. A plurality of swirler vanes 16 are disposedcircumferentially around the inner peripheral surface 18 of fuel swirler10 proximate the inlet end 12. The swirler vanes 16 are attached to ahub 26. The hub 26 surrounds the main fuel nozzle 20.

The fuel swirler 10 surrounds a portion of a main fuel nozzle 20proximate main fuel injection ports 22. The fuel swirler 10 ispositioned such that the swirler vanes 16 are upstream of the main fuelinjection ports 22. The inlet end 12 is adapted to receive compressedair 23 from the compressor section of the engine (not shown) and tochannel it into the swirler vanes 16. The swirler vanes 16 disrupt theflow of the compressed air 23 through the swirler 10 to promote mixingof the air 23 with fuel introduced through the ports 22. The outlet end14 of the swirler 10 is adapted to fit into a swirler extension sleeve24.

In prior art systems, the fuel swirler 10 is attached to a combustorsupport frame 30 by two support pins 28. Each support pin 28 is weldedat one end to the combustor support frame 30 and at the other end to theswirler body 11. However, experience has revealed problems with such anattachment scheme. The support pins 28 are subjected to vibrationalforces generated during combustion; consequently, the support pins 28and/or the welds are susceptible to fatigue-induced cracking. Theformation of cracks in the support pins 28 or welds has promptedunscheduled engine shut down and has lead to costly and protractedrepair and replacement.

Further, attachment of the support pins 28 to the swirler 10 andcombustor support frame 30 by welding can complicate the combustorassembly process. During post-welding cool down, the swirlers 10 havebeen known to move out of their design position. Combustor performancecan be adversely affected if the swirlers 10 and the main fuel nozzle 20are not properly aligned. Thus, the assembly process may requireadditional steps to realign these components. One realignment methodincludes physically bending the swirler 10 into the design position.However, such cold bending can cause residual stresses to develop in thepins 28, and such stresses can further reduce the fatigue life of theswirler 10 and/or the pins 28. Thus, there is a need for a swirlerattachment system that minimizes the foregoing concerns.

SUMMARY OF THE INVENTION

Aspects of the invention are directed to a swirler for a turbine enginecombustor. The swirler includes an elongated swirler body that has aninlet end and an outlet end. The swirler body defines a longitudinalaxis. The swirler body has an outer peripheral surface and an innerperipheral surface. A plurality of swirler vanes extend radially inwardfrom the inner peripheral surface of the swirler body. The vanes arearrayed about the inner peripheral surface of the swirler proximate theinlet end.

A bracket is secured to the outer peripheral surface of the swirlerbody. The bracket projects substantially radially outward from theswirler body to a radially distal end. The bracket includes an openingadapted for removably receiving a fastener. In one embodiment, theopening and the fastener can be threaded. Thus, the opening and fastenercan be in threaded engagement.

The opening extends radially inward from the radial distal end of thebracket. The bracket is located on the swirler body in a region definedbetween the inlet end and an axially central region of the swirler body.In one embodiment, the bracket and the swirler body can be unitary.Alternatively, the bracket and the swirler can be separate. In suchcase, the bracket can be secured to the swirler body by welding. Thebracket can have a radially inner end and a radially outer end. Theradially inner end of the bracket can substantially matingly engage theouter peripheral surface of the swirler body.

In one embodiment, there can be a second bracket. The second bracket canbe secured to the outer peripheral surface of the swirler body. In suchcase, the second bracket can be located in a region defined between theinlet end and an axially central region of the swirler body.Alternatively, the second bracket can be located on an extension sleevethat is secured to the swirler body. The outlet end of the swirler bodycan be received within the sleeve.

Aspects of the invention further relate to a swirler attachment system.The system includes a combustor support frame, a swirler, a bracket, anda fastener. The combustor support frame has an inner peripheral surfaceand an outer peripheral surface. A radial hole extends through the framefrom the inner peripheral surface to the outer peripheral surface.

The swirler includes an elongated swirler body that has an inlet end andan outlet end. In addition, the swirler body has an outer peripheralsurface and an inner peripheral surface. Further, the swirler bodydefines a longitudinal axis. The bracket is secured to the outerperipheral surface of the swirler body. The bracket projectssubstantially radially outward from the swirler body to a radiallydistal end. The bracket includes an opening adapted for removablyreceiving a fastener. The opening extends radially inward from theradial distal end of the bracket. The bracket is located on the swirlerbody in a region defined between the inlet end and an axially centralregion of the swirler body.

The fastener extends through the radial hole in the frame. The fasteneris attached within with the opening in the bracket so as to secure theswirler to the support frame. In one embodiment, the fastener can be athreaded bolt. Further, the radial hole in the bracket can be threaded.Thus, the opening can threadably engage the bolt. in one embodiment, thefastener and/or the opening in the bracket can include a special threadform to impede unwanted travel of the fastener.

The radial hole can be adapted to provide a substantially dowel fit withthe bolt. In such case, movement of the bolt within the opening can besubstantially minimized. Further, a lock washer can be provided andoperatively positioned between the fastener and the outer peripheralsurface of the combustor support frame. The lock washer can impedeunwanted travel of the fastener.

The radial distal end of the bracket substantially engages the innerperipheral surface of the combustor support frame. The inner peripheralsurface of the combustor support frame can have a seating surface. Theseating surface can be adapted for substantially mating engagement withthe radial distal end of the bracket. The seating surface can be definedby a recess in the inner peripheral surface of the combustor supportframe. Alternatively, the seating surface can be defined by a protrusionextending radially inward from the inner peripheral surface of thecombustor support frame.

The system can include a swirler base plate that can be secured to thecombustor support frame. The base plate can include an opening. Theaxial downstream end of the swirler can be positioned substantiallyadjacent to the opening. Thus, the swirler and the opening can be influid communication. Alternatively, the axial downstream end of theswirler can be received within the opening.

In one embodiment, the system can further include a combustor supportplate and a swirler base plate. The combustor support plate can includean opening for receiving the axial downstream end of the swirler. In oneembodiment, the combustor support plate can be made of four panels. Theswirler base plate can include an opening. The opening in the supportplate can be disposed axially upstream of and in substantial alignmentwith the opening in the base plate. A portion of the swirler can bereceived within the opening in the support plate. The swirler base platecan be attached to the combustor support frame, and the combustorsupport plate can be attached to the combustor base plate. A portion ofthe swirler can extend through the opening in the support plate suchthat the axial downstream end of the swirler can be positionedsubstantially proximate to the opening in the base plate. A peripheralgap can be formed between the end of the swirler and the base plate. Asa result, air can pass through the gap so as minimize flashbackpotential.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a prior main fuel swirler.

FIG. 2 is a cross-sectional view of a fuel swirler according to aspectsof the invention.

FIG. 3 is a side elevational view of a fuel swirler according to aspectsof the invention.

FIG. 4 is a cross-sectional view of a swirler attachment systemaccording to aspects of the invention.

FIG. 5A is a close up view of an interface between the swirler bracketand the combustor support frame according to aspects of the invention.

FIG. 5B is a close up view of another interface between the swirlerbracket and the combustor support frame according to aspects of theinvention.

FIG. 6 is a cross-sectional view of the swirler attachment systemaccording to aspects of the invention, showing a swirler support plateprovided near the axial downstream end of the swirler.

FIG. 7 is a view of bolted swirlers and a support plate system accordingto aspects of the invention, viewed from line 7-7 in FIG. 6.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Embodiments of the present invention are directed to swirler attachmentsystems. Embodiments of the invention will be explained in the contextof one possible system, but the detailed description is intended only asexemplary. Embodiments of the invention are shown in FIGS. 2-7, but thepresent invention is not limited to the illustrated structure orapplication.

A fuel swirler assembly 40 according to embodiments of the invention isshown in FIGS. 2 and 3. The swirler 40 can include a swirler body 41having an inlet end 42 and an outlet end 44. The swirler 40 can define alongitudinal axis 46. The swirler body 41 can be generally cylindricalin conformation, but the swirler body 41 can have any shape includingrectangular or polygonal, as dictated by design considerations andperformance requirements. The swirler body 41 can have an outerperipheral surface 48 and an inner peripheral surface 50. As shown, theswirler body 41 can taper from the inlet end 42 to the outlet end 44,but, in some embodiments, the swirler body 41 may not be tapered.

The swirler assembly 40 can include a swirler extension sleeve 52 havinga proximal axial end 54 and a distal axial end 56. As used in connectionwith the swirler extension sleeve 52, the terms “proximal” and “distal”refer to the position of the ends 54, 56 of the sleeve 52 relative tothe swirler body 41. The sleeve 52 can be generally cylindrical inconformation. The outlet end of the swirler body 41 can be positioned soas to extend into the proximal end 54 of the sleeve 52. The sleeve 52and the swirler body 41 can be joined together, such as by welding.

It will be appreciated that the inlet 42 of the swirler body 41 candefine the axial upstream end 60 of the swirler assembly 40, and thedistal end 56 of the sleeve 52 can define the axial downstream end 62 ofthe swirler assembly 40. However, in some instances, the swirlerassembly 40 may not include a sleeve 52. In such case, the outlet end 44of the swirler body 41 can define the axial downstream end 62 of theswirler assembly 40. Thus, when the axial downstream end 62 of theswirler 40 is referenced herein, it will be understood that such termcan encompass either of the above possibilities.

According to embodiment of the invention, the fuel swirler 40 caninclude a bracket 64 to facilitate attachment of the swirler 40 to acombustor support frame 66. The bracket 64 can project substantiallyradially outward (relative to the longitudinal axis 46) from the outerperipheral surface 48 of the swirler body 41. The bracket 64 can be aseparate component that is secured to the outer peripheral surface 48 ofthe swirler body 41. For example, the bracket 64 can be secured to theswirler body 41 by welding. Alternatively, the bracket 64 and theswirler body 41 can be a unitary structure, such as by casting. Thebracket 64 can be made of any of a number of materials, but it ispreferred if the bracket 64 is made of the same material as the swirlerbody 41 and/or the combustor support frame 66. In one embodiment, thebracket 64 can be made of stainless steel, such as 304 stainless steel.

The bracket 64 can have any of a number shapes. In one embodiment, thebracket 64 can have a substantially cylindrical body 68 with a pair ofattachment fins 70 on each side, as shown in FIGS. 2 and 3. The body 68may or may not be tapered. Again, the bracket 64 shown in FIGS. 2 and 3is just one of many possible configurations, and a bracket 64 accordingto aspects of the invention is not limited to any particular shape.

The bracket 46 can have a radially proximal end 72 and a radially distalend 74 relative to the longitudinal axis 46 of the swirler 40. When thebracket 64 is a separate component, it is preferred if the radiallyproximal end 72 of the bracket 64 is machined, for example, to beslightly curved, so as to substantially matingly engage a curved outerperipheral surface 48 of the swirler body 40.

Each swirler 40 can have a single bracket 64 for attaching the swirler40 to the combustor support frame 66. The bracket 64 can be provided atvarious locations along the swirler body 41. In one embodiment, thebracket can be provided near the inlet end 42 of the swirler body 41.Preferably, the bracket 64 is located within an axial upstream region 76of the swirler body 41. The region 76 can be defined between the inletend 42 of the swirler body 41 and a substantially axially centralportion of the swirler body 41. In some instances, there can be morethan one bracket 64 associated with the swirler 40. In one embodiment,there can be two brackets 64 associated with the swirler 40. In suchcase, the additional bracket (not shown) can be provided on the swirlerbody 41, preferably also located within the axial upstream region 76.Alternatively, an additional bracket can be attached to the sleeve 52near the proximal end 54. While being axially spaced apart, the brackets64 can be substantially peripherally aligned, or the brackets 64 can beperipherally offset.

The bracket 64 can include a hole 78, which can be threaded and providedby, for example, drilling and tapping. The hole 78 can extendsubstantially radially inward from the radially distal end 74 of bracket64 toward the radially proximal end 72 of the bracket 64. The radiallydistal end 74 of the bracket 64 can be machined so as to substantiallymatingly engage the combustor support frame 66, and thereby facilitateproper alignment of the swirler assembly 40. In embodiments where thebracket 64 is a separate part that is welded to the swirler body 41, themachining of the radially distal end 74 and the inclusion of thethreaded hole 78 can be completed after the welding operation and afterthe parts have cooled. Thus, any potential warpage caused by the weldingcan be compensated for without introducing residual stresses to theswirler assembly 40.

Again, the swirler assembly 40 can be attached to the combustor supportframe 66, which can be any suitable stationary structure in thecombustor to which the fuel swirlers 10 can be attached. The combustorsupport frame 66 can have an outer peripheral surface 80 and an innerperipheral surface 82. For each swirler 40, the combustor support frame66 can provide a seating surface 84 for substantially mating engagementwith the radial distal end 74 of the bracket 64.

The seating surface 84 can be a localized precision machined area. Theseating surface 84 can include any of a number of surface features, suchas protrusions, to engage the radial distal end 74 of the bracket 64. Inone embodiment, the seating surface 84 can be defined by a recess 86 forreceiving a portion of the bracket 64 including at least the radiallydistal end 74, as shown in FIG. 5A. The recess 86 can extend radiallywithin the combustor support frame 66, from the inner peripheral surface82 toward the outward peripheral surface 80. The recess 86 can beincluded in the combustor support frame 66 by machining. The recess 86can have any of a number of shapes and, preferably, the recess 86substantially corresponds to the shape of the distal end 74 of thebracket 64. In one embodiment, the recess 86 can be substantiallycylindrical. The recess 86 can include the seating surface 84 and atleast one sidewall 88. It is preferred if the seating surface 86 ismachined for substantially mating engagement with the distal end 74 ofthe bracket 64. Similarly, the sidewall 86 can be machined foradditional substantially mating engagement with the bracket 64.

In another embodiment, the seating surface 84 can be defined by aprotrusion 85 provided on the inner peripheral surface 82 of thecombustor support frame 66, as shown in FIG. 5B. The protrusion 85 canextend radially inward from the inner peripheral surface 82. Theprotrusion 85 can be formed in the combustor support frame 66 by, forexample, machining or casting. The protrusion 85 can have any of anumber of shapes and, preferably, the protrusion 85 substantiallycorresponds to the shape of the distal end 74 of the bracket 64. In oneembodiment, the protrusion 85 can be substantially cylindrical.

A series of radial holes 90 can be machined in the combustor supportframe 66 to provide the required circumferential location of theswirlers 40 about the frame 66. The radial holes 90 can extend from theouter peripheral surface 80 through the inner peripheral surface 82 ofthe combustor support frame 66, opening to the seating surface 84.Preferably, the radial hole 90 is substantially centered within theseating surface 84. The radial holes 90 can have any of a number ofshapes, but preferably they are substantially circular. Naturally, thenumber of seating surfaces 84 and/or radial holes 90 provided in thecombustor support frame 66 will depend on the number of fuel swirlers 40used and the number of brackets 64 associated with each swirler 40. Inone embodiment, there can be eight radial holes 90 and seating surface84 pairs arranged circumferentially about the combustor support frame66.

Thus, when the distal end 74 of the swirler bracket 64 is positionedagainst the seating surface 84, the threaded opening 78 in the bracket64 can be substantially aligned with a respective radial hole 90 in thecombustor support frame 66. A fastener can be used to attach the swirler40 to the combustor support frame 66. In one embodiment, the fastenercan be a bolt 92. In such case, the bolt 92 can be inserted from theouter peripheral surface 80 of the combustor support frame 66, such thatthe head 94 of the bolt 92 operatively engages the outer peripheralsurface 80 of the combustor support frame 66. The shaft 96 of the bolt92 can extend through the radial hole 90 and into threaded engagementwith opening 78 in the bracket 64. As the bolt 92 is tightened, theswirler 40 can be pulled into the design position. Preferably, theradial holes 90 in the frame 66 are sized so as to substantially form adowel fit with the bolt 92, thereby minimizing movement of the bolt 92within the opening 78. Dowel fit is intended to mean a that a portion ofthe bolt 92 and the radial holes 90 are tightly toleranced. Movement ofthe bolt 92 can alter the position of the swirler 40 and affectcombustor performance.

In some instances, it may be desirable to provide additional measures toprevent the bolt 92 from moving or otherwise coming loose during engineoperation. To that end, a lock washer 98 can be positioned between thehead 94 of the bolt 92 and the outer peripheral surface 80 of thecombustor support frame 66. Alternatively or in addition, the bolt 92and/or the threaded opening 78 in the bracket 64 can be provided with aspecial thread form so as to substantially lock the bolt 94 in place.Yet another possibility for bolt retention is to weld the bolt 92 to thecombustor support frame 66. It will be appreciated that the above aremerely a few examples of the various manners in which the fastener canbe substantially locked in place.

The bracket 64 can be used to support at least the upstream end 60 ofthe swirler assembly 40. Additional support for the axial downstream end62 of the swirler 40 can be provided as well. Support of the downstreamend 62 of the swirler 40 can be achieved in numerous ways. For instance,as noted above, an additional bracket 64 can be provided on the swirler40. In such case, no further support may be needed for the axialdownstream end 62 of the swirler 40. In such case, the axial downstreamend 62 of the swirler 40 can be positioned substantially adjacent to aswirler base plate 100. “Substantially adjacent” is intended to meandirect contact between the downstream end 62 of the swirler 64 and thebase plate 100 as well as these components being spaced apart.

The base plate 100 can be anchored to the combustor support frame 66and/or a pilot cone 102 by, for example, welding. A plurality ofopenings 104 can be provided in the base plate 100 for interfacing withthe axial downstream end 62 of the swirler 40. The opening 104 can be athrough hole or it can be the product of bends in the plate 100. Whilethe term “plate” may connote a flat plate, embodiments of the inventionare not limited to flat plates as the base plate 100 can include any ofa number of curves and bends, among other non-flat features. Typically,the base plate 100 can be shaped from a metal sheet and the openings 104can be formed in a drawing process.

Especially in cases where only one bracket 64 is provided on the swirler40, there are various options for supporting the downstream end 62 ofthe swirler 40. In one embodiment, the downstream end 62 of the swirler40 can be positioned within the opening 104 in the swirler base plate100. The details and benefits of such an arrangement are described indetail in U.S. Pat. No. 6,705,087, which is incorporated herein byreference.

Alternatively, a swirler support plate 106 can be provided to supportthe downstream end 62 of the swirler 40, as shown in FIG. 6. The supportplate 106 can be secured to the base plate 100 by, for example, welding.In one embodiment, the support plate 106 can have a generally S-shapedprofile. The support plate 106 can be a single plate or it can bemultiple plates. For instance, the support plate 106 can include fourindividual panels, only two of such panels 106 a, 106 b being shown inFIG. 7. The support plate 106 can provide a plurality of openings 108for receiving the axial downstream end 62 of each swirler 40, such asthe distal end 56 of the swirler sleeve 52.

The support plate 106 can provide advantages in reducing the potentialfor flashback, which occurs when the combustion flame travels upstreamand attaches to the base plate 100 or the downstream end 62 of theswirler 40. Flashback can damage these components and interfere withefficient combustor operation. One way to reduce flashback potential isto provide a film of air on the outside of the swirler 40. Because theaxial downstream end 62 of the swirler 40 can be supported by the plate106, a gap 110 can be provided between the base plate 100 and the axialdownstream end 62 of the swirler 40. Compressed air can be supplied fromthe compressor to the gap 110 by one or more cutouts 112 provided in thesupport plate 106. The gap 110 allows a film of air to develop over thedownstream end 62 of the swirler 40 and the base plate 100, therebydiscouraging flashback.

It will be appreciated that, in comparison to the prior welded pinapproach, embodiments of the invention described above can reduce thetime and cost associated with installing fuel swirlers in the combustorsection. The system can avoid the issues associated with the weldingprocess including, for example, distortion and material defects. Theattachment system according to aspects of the invention can provideadvantages during repair service as the system permits easy replacementof individual swirlers and does not require special tools or fixtures.Further, the design can improve reliability in manufacturing and reduceservice cost and time in replacing a swirler. There is also potentialfor improved swirler alignment because there is no weld distortionintroduced at a final assembly.

The foregoing description is provided in the context of one possiblesystem for attaching fuel swirlers to a combustor support frame. It willof course be understood that the invention is not limited to thespecific details described herein, which are given by way of exampleonly, and that various modifications and alterations are possible withinthe scope of the invention as defined in the following claims.

1. A swirler for a turbine engine combustor comprising: an elongatedswirler body having an inlet end and an outlet end, the swirler bodydefining a longitudinal axis, the swirler body having an outerperipheral surface and an inner peripheral surface; a plurality ofswirler vanes extending radially inward from the inner peripheralsurface of the swirler body, the vanes being arrayed about the innerperipheral surface of the swirler proximate the inlet end; and a bracketsecured to the outer peripheral surface of the swirler body andprojecting substantially radially outward therefrom to a radially distalend, the bracket including an opening adapted for removably receiving afastener, the opening extending radially inward from the radial distalend of the bracket, wherein the bracket is located on the swirler bodyin a region defined between the inlet end and an axially central regionof the swirler body.
 2. The swirler of claim 1 wherein the bracket andthe swirler body are unitary.
 3. The swirler of claim 1 wherein thebracket is secured to the swirler body by welding.
 4. The swirler ofclaim 3 wherein the bracket includes a radially inner end and a radiallyouter end, and wherein the radially inner end of the bracketsubstantially matingly engages the outer peripheral surface of theswirler body.
 5. The swirler of claim 1 further including a secondbracket secured to the outer peripheral surface of the swirler body,wherein the second bracket is located in a region defined between theinlet end and an axially central region of the swirler body.
 6. Theswirler of claim 1 further including a second bracket and an extensionsleeve, wherein the sleeve is secured to the swirler body, wherein theoutlet end of the swirler body is received within the sleeve, andwherein the second bracket is secured to the extension sleeve.
 7. Theswirler of claim 1 wherein each of the opening and the fastener isthreaded, wherein the opening and fastener are in threaded engagement.8. A swirler attachment system comprising: a combustor support framehaving an inner peripheral surface and an outer peripheral surface, aradial hole extending through the frame from the inner peripheralsurface to the outer peripheral surface; a swirler having an elongatedswirler body having an inlet end and an outlet end, the swirler bodydefining a longitudinal axis, the swirler body having an outerperipheral surface and an inner peripheral surface; a bracket secured tothe outer peripheral surface of the swirler body and projectingsubstantially radially outward therefrom to a radially distal end, thebracket including an opening adapted for removably receiving a fastener,the opening extending radially inward from the radial distal end of thebracket, wherein the bracket is located on the swirler body in a regiondefined between the inlet end and an axially central region of theswirler body; and a fastener extending through the radial hole in theframe and attached within with the opening in the bracket so as tosecure the swirler to the support frame, wherein the radial distal endof the bracket substantially engages the inner peripheral surface of thecombustor support frame.
 9. The system of claim 8 further including aseating surface on the inner peripheral surface of the combustor supportframe, wherein the seating surface is adapted for substantially matingengagement with the radial distal end of the bracket.
 10. The system ofclaim 9 wherein the seating surface is defined by one of a recess in theinner peripheral surface of the combustor support frame and a protrusionextending radially inward from the inner peripheral surface of thecombustor support frame.
 11. The system of claim 8 further including aswirler base plate secured to the combustor support frame, the baseplate including an opening, wherein the axial downstream end of theswirler is positioned substantially adjacent to the opening, whereby theswirler and the opening are in fluid communication.
 12. The system ofclaim 8 further including a swirler base plate secured to the combustorsupport frame, the base plate including an opening, wherein the axialdownstream end of the swirler is received within the opening.
 13. Thesystem of claim 8 further including: a combustor support plate, whereinthe support plate includes an opening for receiving the axial downstreamend of the swirler; and a swirler base plate including an opening,wherein the opening in the support plate is disposed axially upstream ofand in substantial alignment with the opening in the base plate, whereina portion of the swirler is received within the opening in the supportplate, wherein the combustor base plate is attached to the combustorsupport frame and the combustor support plate is attached to the swirlerbase plate.
 14. The system of claim 13 wherein a portion of the swirlerextends through the opening in the support plate such that the axialdownstream end of the swirler is positioned substantially proximate tothe opening in the base plate, wherein a peripheral gap is formedbetween the end of the swirler and the base plate, whereby air can passthrough the gap so as minimize flashback potential.
 15. The system ofclaim 13 wherein the combustor support plate is made of four panels. 16.The system of claim 8 wherein the fastener is a threaded bolt.
 17. Thesystem of claim 8 wherein the radial hole is adapted to provide asubstantially dowel fit with the fastener, whereby movement of thefastener within the hole is substantially minimized.
 18. The system ofclaim 8 further including a lock washer operatively positioned betweenthe fastener and the outer peripheral surface of the combustor supportframe, whereby the lock washer impedes unwanted travel of the fastener.19. The system of claim 8 wherein at least one of the fastener and theopening in the bracket includes a special thread form, whereby unwantedtravel of the fastener is impeded.
 20. The system of claim 8 wherein theopening is threaded and the fastener is a threaded bolt, wherein theopening threadably engages the bolt.